Samoa Air(NEW YORK) -- If it's an April Fools' Day joke, it's an awfully elaborate one. If not, Samoa Air has become the first airline in the world to do what was previously unthinkable: Charge passengers by weight.

Not that the idea hasn't been floated -- several times -- in the past. In fact, ABC News reported just last week a Norwegian economist was the latest to float the idea of an airline "fat tax."

The Samoa Air homepage reads: "We at Samoa Air are keeping airfares fair, by charging our passengers only for what they weigh. You are the master of your Air'fair', you decide how much (or little) your ticket will cost. No more exorbitant excess baggage fee's [sic], or being charged for baggage you may not carry. Your weight plus your baggage items, is what you pay for. Simple."

"Airplanes don't run on seats, they run on weight," Samoa Air's Chief Executive, Chris Langton, told Radio Australia.

A section of the airline's website titled "How does pay what you weigh work?" outlines the steps in determining a passengers final airfare:

Step 4. You travel happy, knowing full well that you are only paying for exactly what you weigh... nothing more.

And if you're wondering how Samoa Air will guard against people entering their high school weight as opposed to their actual weight, the airline says passengers will be weighed at the airport.

"Booking a flight with us is as easy as inputting your approximate weight into our online booking engine (don't worry, we will weigh you again at the airport) -- you then can prepay your 'guesstimate', guaranteeing you that much weight is allocated to you for that flight," the site reads.

"People who have been most pleasantly surprised are families because we don't charge based on seat requirement even though a child is required to have a seat," Langton said. "We just weigh them. So a family of two adults and maybe a couple of mid-sized kids or younger children can travel for considerably less than what they were being charged before."

Samoa Air flies from Samoa to American Samoa, North Tonga, Niue, North Cook Islands and French Polynesia. The airline does not fly large commercial aircraft, but rather small planes that are more susceptible to weight variances.

And while Langton said there's "no doubt in my mind this is the concept of the future," it will likely take major carriers quite awhile to warm up to the concept, if they ever do.